[Zope] Check uploaded file for valid contents

[Andreas Tille]

Hello,

I wonder if there is an elegant method to check a file which is intended
to be stored as (Ext)File in the ZODB according to the validity of its
contents.  The reason is thatr I have to store some PDF files but I have
users who do not really know the difference between DOC and PDF.  I want
to refuse DOCs (or any other non-PDF) to enforce users to upload just PDF.


Kind regards

       ANdreas.